Fuel system help!!!!!
WhitexTrashxKid
12-22-2003, 03:06 AM
I need a whole lotta help here!!! i have gone through and replaced like 90% of the fuel system in my 1987 fiero. It hasnt run in 4 years and i am just now bringin my baby back to life.Anyways, its not getting the signal to the tbi like it should be and i cant figure out why. i replaced the fuel pump relay,fuel pump,and the throttle body injector itself(used)
I stilll am not getting a signal. I thought it could be the ecm but i changed that to then switched back to the original on when she still wouldnt fire.Now it does run, only when i run a hot wire directly from the tbi to the battery,but of course it runs like shit but it still runs showing me im missing something somewhere.it's a four cylynder by the way. im sure most of you knew that anyways because of the tbi.
I stilll am not getting a signal. I thought it could be the ecm but i changed that to then switched back to the original on when she still wouldnt fire.Now it does run, only when i run a hot wire directly from the tbi to the battery,but of course it runs like shit but it still runs showing me im missing something somewhere.it's a four cylynder by the way. im sure most of you knew that anyways because of the tbi.
Blue02R6
12-22-2003, 03:52 AM
Perhaps the wire from the ECM is shorted or corroded. (<-Spelling?)
WhitexTrashxKid
12-22-2003, 04:09 PM
ok i was wrong i think, if im not getting a signal it shouldnt work at alll so obviously im not getting power because it doest shoot gas continually when i hoook it up direct to the battery it shoots when its supposed to so i think i am not getting power to the throttle body so could you help me there? p.s. i hate fuel injection way above my head!
SEP
02-27-2004, 11:59 PM
Were you able to solve this. I have the same problem and can't seem to find anyone who knows what is causing this.
goatnipples2002
06-21-2004, 03:31 PM
If you need a new fuel pump get the pump from the 89 firebird anniversary edition. It direct bolts and flows 40-50 (however you measure fuel flow).
coop8267
06-21-2004, 10:24 PM
hhmmmm thats a tough one. i would trace the two wires that hook on the injector and see if one is screwed. like blue said
Ragtop_Renegade
06-22-2004, 02:14 PM
ok i was wrong i think, if im not getting a signal it shouldnt work at alll so obviously im not getting power because it doest shoot gas continually when i hoook it up direct to the battery it shoots when its supposed to so i think i am not getting power to the throttle body so could you help me there? p.s. i hate fuel injection way above my head!
No way!! you're already doing a great job!! You narrowed the problem down to three main causes:
1. No fuel flow
2. injector does not work
3. ecm signal not present at injector.
Following that, you've already ruled out 1 & 2 so lets look at the causes for 3
1. no power to ECM
2. ECM faulty
3. Blown fuse in TBI power circuit
4. wire damage between ecm and TBI unit
We know we can rule out 1 here because the coil fires, without the ecm having power that isn't possible.
We know the injector does fire properly if an outside power source is applied... because the ecm works by grounding the injector to fire it, it seems you've found you main problem, you have a complete ground but no power to the injector.
Check the fuse box, if all fuses are ok rule out 3, if not, problem solved
Check wires with an ohm meter, clean any corrosion on connectors - if wires are ok, rule out 4. If not, problerm solved.
If all else fails, power is cut off inside ecm. replace ecm.
No way!! you're already doing a great job!! You narrowed the problem down to three main causes:
1. No fuel flow
2. injector does not work
3. ecm signal not present at injector.
Following that, you've already ruled out 1 & 2 so lets look at the causes for 3
1. no power to ECM
2. ECM faulty
3. Blown fuse in TBI power circuit
4. wire damage between ecm and TBI unit
We know we can rule out 1 here because the coil fires, without the ecm having power that isn't possible.
We know the injector does fire properly if an outside power source is applied... because the ecm works by grounding the injector to fire it, it seems you've found you main problem, you have a complete ground but no power to the injector.
Check the fuse box, if all fuses are ok rule out 3, if not, problem solved
Check wires with an ohm meter, clean any corrosion on connectors - if wires are ok, rule out 4. If not, problerm solved.
If all else fails, power is cut off inside ecm. replace ecm.
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